Call forwarding is a feature commonly available through many telephone companies that enables a subscriber to automatically have his telephone calls forwarded to another telephone number from the telephone line to which they were initially directed. In its basic implementation, a subscriber dials a feature code from the telephone associated with the subscribed-to service and inputs the forwarding telephone number to which he wants subsequent calls directed. The central office switch recognizes the feature code and the telephone line from which the subscriber has dialed, and the central office switch thereafter redirects calls from the subscriber's telephone line to the forwarding telephone number. For remote call forwarding, the subscriber is not at the phone which is associated with the feature.
Two methods are commonly available: a network service or using specialized subscriber equipment connected to the subscriber's telephone line. As a network service, in order to invoke call forwarding to the telephone at the subscriber's current location, the subscriber makes an actual phone call to a designated special telephone number associated with his local switch, provides the number of the telephone associated with the subscribed-to feature, inputs a PIN to prevent unauthorized call forwarding, and then inputs a feature code designated for call forwarding. The telephone number from which the subscriber initiates the procedure is recognized by the network and the subscriber's central office switch thereafter directs calls from the subscriber's telephone line to the telephone line from which the remote call forwarding feature has been invoked.
Using specialized subscriber equipment, in order to invoke remote call forwarding, the subscriber places a call to his specialized equipment, inputs a PIN to prevent unauthorized call forwarding, and then inputs the telephone number to which calls should be forwarded. The specialized equipment then connects to the subscriber's telephone line and dials the call forward feature code and forwarding telephone number following the same procedure as basic call forwarding. The central office switch recognizes the feature code and the telephone line from which the subscriber's specialized equipment has dialed and the central office switch thereafter redirects telephone calls from the subscriber's telephone line to the forwarding telephone number.
Both basic call forwarding and remote call forwarding are features that can be associated with a subscriber's home telephone in which calls are redirected by the subscriber's switch in the local exchange office. Basic call forwarding and remote call forwarding are also features that can be associated with a telephone connected to a PBX in a corporate environment. As described above, for basic call forwarding the user enters a feature code from his telephone together with the telephone number to which calls are to be directed. For remote call forwarding, the user must dial a specific extension on the PBX, enter his own extension number, and a PIN. Once call forwarding is invoked, the PBX thereafter places an outbound telephone call to the forwarding telephone number in response to an inbound call directed to the forwarder's telephone number and bridges the inbound and outbound telephone calls.
A user of a mobile cellular telephone can invoke remote call forwarding to his cellular telephone from his home or office telephone in a manner described above. Thus, as described above, the user must dial a special telephone number, which number is either associated with his local switch or PBX, and then enter his telephone number and a PIN. Disadvantageously, such a procedure over a wireless cellular network can provide security problems that are not present when remotely invoking a call forward feature from a telephone on the secure wire-line telephone system. Specifically, since a user's touch-tone inputs on the cellular phone can possibly be intercepted, an eavesdropper could illegal obtain a user's telephone number and password and then remotely invoke the call forwarding feature to forward calls to some desired telephone number.
An object of the present invention is to securely invoke a remote call forwarding feature for a subscriber's wire-line telephone from the subscriber's cellular phone.
An additional object of the present invention it to invoke a remote call forwarding feature from a subscriber's cellular phone in a manner that does not require the subscriber to place a separate phone call and to input a PIN.